X is a variable to find it you need to isolate it(get it by itself)
Answer:
The volume in such a package is 27648 in³
Step-by-step explanation:
Consider the provided information.
Postal regulations specify that a parcel sent by priority mail may have a combined length and girth of no more than 144 in.
Let the dimension are x by x by y.
Where x is the variable for the square base package and y is the variable for length.
Thus l=x, b=x and h=y
Then the volume of the box is:
(∵V=lbh)
The maximum combined length and girth is 144.
Therefore, 

Substitute the value of y in volume of the box.



Substitute V'(x)=0.



Now apply second derivative test.

(Min)
(Max)
Hence, the maximum volume is at x=24
If x=24 then 
Substituting value of x = 24 and y = 48
gives 27648.
Hence, the volume in such a package is 27648 in³
All the sides are 3 since volume is L*W*H you get 3*3*3 = 9*3 = 27
Answer:
Step-by-step explanation:
b
The expression that we need to get is:

So the correct option is the second one.
<h3>Which expression gives the number of gallons of stain Bradley will need?</h3>
We know that 1 gallon is enough to cover 200 ft².
We have two rectangular areas, one of:
23 feet by 10.4 feet, and other of 10.5 feet by 7.2 feet.
Then the total area is:
A = (23 ft)*(10.4 ft) + (10.5ft)*(7.2 ft)
The number of gallons needed is given by the quotient between the area that we want to cover, and the area that covers one gallon, so the expression is:

So the corerect option is the second one.
If you want to learn more about algebraic expressions:
brainly.com/question/4344214
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